1. Introduction
The Extech 382252 is a comprehensive Earth Ground Resistance Tester Kit designed for accurate measurement of earth ground resistance. This kit provides three selectable ranges for earth ground resistance: 20 Ohms (Ω), 200 Ohms (Ω), and 2000 Ohms (Ω). Beyond earth ground testing, the device also functions as a multimeter, capable of measuring AC/DC Voltage, Resistance, and Continuity. It features automatic zero adjustment for ease of use. This manual provides detailed instructions for the safe and effective operation, maintenance, and troubleshooting of your Extech 382252.
2. Consignes de sécurité
Avertissement: Improper use of this meter can cause damage, shock, injury, or death. Read and understand all safety information and operating instructions before using this instrument. Always adhere to local and national safety codes.
- Ne dépassez pas les limites d'entrée maximales pour aucune fonction.
- Faites preuve d'une extrême prudence lorsque vous travaillez sur des circuits électriques sous tension.
- Ensure the meter is in good working condition and free from damage before use.
- Utilisez toujours la fonction et la plage de mesure appropriées.
- Remplacez les piles lorsque le voyant de batterie faible s'allume afin de garantir des mesures précises.
- Keep hands and fingers away from test probe tips when making measurements.
- Ne pas utiliser l'appareil de mesure dans des atmosphères explosives ou en présence de gaz ou de poussières inflammables.
3. Contenu du colis
Vérifiez que tous les articles sont présents et non endommagés lors du déballage :
- Extech 382252 Earth Ground Resistance Tester
- Test Leads (set)
- Auxiliary Earth Bars (2 pieces)
- Mallette de transport
- Protective Rubber Holster
- Piles AA 1.5 V (6 pièces)

Image 1: The Extech 382252 Earth Ground Resistance Tester Kit, showing the main unit, test leads, two auxiliary earth bars, and the carrying case.
4. caractéristiques du produit
The Extech 382252 offers the following key features:
- Earth Ground Resistance measurement in three ranges: 20Ω, 200Ω, and 2000Ω.
- Vol AC/DCtagcapacités de mesure.
- Resistance and Continuity testing functions.
- Automatic zero adjustment for accurate readings.
- Grand écran LCD facile à lire.
- Fonction de maintien des données pour figer les valeurs affichées.
- Rétroéclairage pour une meilleure visibilité en conditions de faible luminosité.
- Durable protective rubber holster.

Illustration 2 : Avant view of the Extech 382252 Earth Ground Resistance Tester, highlighting its display, function dial, and control buttons.
5. Installation
5.1 Installation de la batterie
- Assurez-vous que le compteur est hors tension.
- Repérez le couvercle du compartiment à piles à l'arrière du compteur.
- Utilisez un tournevis pour retirer la ou les vis qui fixent le couvercle.
- Insert six (6) 1.5V AA batteries, observing correct polarity (+/-).
- Remettez le couvercle du compartiment à piles en place et fixez-le avec la ou les vis.
5.2 Connexion des cordons de test
Connect the test leads to the appropriate input jacks on the meter for the desired measurement function. For earth ground resistance testing, specific connections involving the auxiliary earth bars will be detailed in the operating instructions.
6. Mode d'emploi
6.1 Mise sous/hors tension
Rotate the function dial from the 'OFF' position to any desired measurement function to power on the meter. To power off, rotate the dial back to the 'OFF' position.
6.2 Automatic Zero Adjustment
The meter features automatic zero adjustment. When selecting a resistance range, the meter will automatically adjust to zero, compensating for lead resistance. Ensure test leads are not shorted or open during this process for accurate zeroing.
6.3 Fonction de maintien des données
Press the 'HOLD' button to freeze the current reading on the display. Press it again to release the hold and resume live readings.
6.4 Fonction de rétroéclairage
Press the backlight button (often indicated by a light bulb icon) to illuminate the display for better visibility in dark environments. Press it again to turn off the backlight.
7. Earth Ground Resistance Measurement
The Extech 382252 uses the 3-wire (or Fall-of-Potential) method for earth ground resistance measurements. This method requires the use of the two auxiliary earth bars provided.
7.1 Measurement Procedure (3-Wire Method)
- Préparation: Assurez-vous que le circuit testé est hors tension et isolé en toute sécurité.
- Placement of Auxiliary Earth Bars:
- Drive the first auxiliary earth bar (P) into the ground at a suitable distance from the earth electrode (E) being tested.
- Drive the second auxiliary earth bar (C) into the ground at a further distance from P, ensuring all three points (E, P, C) are in a straight line. Typical distances are 5-10 meters (15-30 feet) between E and P, and P and C, but may vary based on soil conditions and electrode size.
- Connexion des cordons de test :
- Connect the 'E' terminal of the meter to the earth electrode under test.
- Connect the 'P' terminal of the meter to the first auxiliary earth bar (P).
- Connect the 'C' terminal of the meter to the second auxiliary earth bar (C).
- Sélectionnez la plage : Rotate the function dial to the desired Earth Ground Resistance range (20Ω, 200Ω, or 2000Ω). Start with the highest range if the resistance value is unknown.
- Effectuer le test : Press the 'TEST' button. The meter will inject a current and measure the voltage drop to calculate the earth ground resistance.
- Lire la mesure : La valeur de la résistance s'affichera sur l'écran LCD.
- Vérifier l'exactitude : For critical measurements, it is recommended to repeat the test with the auxiliary earth bars placed at slightly different distances to ensure the reading is stable and accurate.
8. Other Measurements
8.1 Volume CA/CCtage Mesure
- Connect the red test lead to the 'V' input jack and the black test lead to the 'COM' input jack.
- Rotate the function dial to the desired ACV (750V AC) or DCV (1000V DC) range.
- Connectez les sondes de test aux bornes du circuit ou du composant à mesurer.
- Lire le voltage valeur sur l'affichage.
8.2 Mesure de résistance
- Assurez-vous que le circuit ou le composant est hors tension.
- Connect the red test lead to the 'V' input jack and the black test lead to the 'COM' input jack.
- Rotate the function dial to the desired Resistance range (e.g., 200Ω, 20kΩ, 200kΩ).
- Connectez les sondes de test aux bornes du composant.
- Lisez la valeur de résistance sur l'écran.
8.3 Essai de continuité
- Assurez-vous que le circuit ou le composant est hors tension.
- Connect the red test lead to the 'V' input jack and the black test lead to the 'COM' input jack.
- Rotate the function dial to the Continuity position (often indicated by a speaker icon).
- Connectez les sondes de test aux bornes du composant ou du fil.
- Un signal sonore indique la continuité (faible résistance). L'écran affichera la valeur de la résistance.
9. Entretien
9.1 Nettoyage
Wipe the meter with a dry, soft cloth. Do not use abrasives or solvents. Periodically clean the test leads and probes to ensure good electrical contact.
9.2 Remplacement de la batterie
Lorsque le témoin de batterie faible s'affiche, remplacez rapidement les piles afin de préserver la précision des mesures. Consultez la section 5.1 pour les instructions d'installation des piles.
9.3 Stockage
If the meter is to be stored for an extended period, remove the batteries to prevent leakage and damage. Store the meter in its carrying case in a cool, dry environment, away from direct sunlight and extreme temperatures.
10. Dépannage
- No Display/Meter Not Powering On: Check battery installation and ensure batteries are fresh. Verify the function dial is not in the 'OFF' position.
- Lectures inexactes : Ensure test leads are properly connected and not damaged. Check battery level. For earth ground resistance, verify proper placement and connection of auxiliary earth bars and ensure good contact with the ground.
- Pas de bip de continuité : Vérifiez la continuité du circuit. Assurez-vous que les cordons de test font bien contact.
- Display Shows 'OL' (Overload): La valeur mesurée dépasse la plage sélectionnée. Veuillez sélectionner une plage supérieure.
Si le problème persiste après avoir suivi ces étapes, contactez le service client.
11. Spécifications
| Spécification | Valeur |
|---|---|
| Marque | Extech |
| Numéro de modèle | 382252 |
| Earth Ground Resistance Ranges | 20Ω, 200Ω, 2000Ω |
| Vol ACtaget gamme | Jusqu'à 750 V CA |
| Vol CCtaget gamme | Jusqu'à 1000V CC |
| Gammes de résistance | 20Ω, 200Ω, 20kΩ, 200kΩ (typical, check device for full ranges) |
| Précision de mesure | +/-0.5% (for certain functions, refer to product manual for specifics) |
| Source d'énergie | 6 piles AA de 1.5 V |
| Poids de l'article | 0.69 kilogrammes (1.52 livres) |
| Dimensions du produit (L x l x H) | 7.9 x 3.6 x 2 pouces |
| Composants inclus | Test leads, 2 earth bars, carrying case, holster, six 1.5V AA batteries |
| Cote de sécurité | CAT III 1000V, CE |
12. Garantie
The Extech 382252 Earth Ground Resistance Tester Kit typically comes with a Garantie limitée de 1 ans from the date of purchase. This warranty covers defects in materials and workmanship under normal use. It does not cover damage resulting from misuse, accident, unauthorized repair, or modification. Please retain your proof of purchase for warranty claims.
13. Assistance
For technical assistance, calibration services, or further information regarding your Extech 382252, please refer to the official Extech website or contact their customer support department. Contact details can usually be found on the manufacturer's websur le site ou dans la documentation fournie avec votre produit.





